noun one who boils.
2. boiler ·noun a vessel in which any thing is boiled.
3. boiler ·add. ·noun a sunken reef; ·esp., a coral reef on which the sea breaks heavily.
4. boiler ·noun a strong metallic vessel, usually of wrought iron plates riveted together, or a composite structure variously formed, in which steam is generated for driving engines, or for heating, cooking, or other purposes.